I started having this sloshing sound, like water going back and forth when I accelerate hard or when I turn round a corner a bit quickly. It sounds like its coming from around the front firewall or the dash, I'm not too sure. But I didn't notice any water in the foot well. Its quite confusing. Any ideas?
Yes I think it makes sense cause I just revved the car up whilst it was stationary and it still made the sound. So although I thought at first that it only occurs when the car is moving, I was wrong, it still does it when its not moving. I'll google it and see what comes up. But I can't understand why its doing it all of a sudden, could it be that there's a broken pipe somewhere and thats how air got in the system?
OK, at first I was going to have you check the glove box for a bottle of 21 year old Scotch, but since it does it sitting still, then I guess that's not the cause.
The sound comes from the operation of the expansion valve, which is right outside the firewall where the refrigerant lines enter to feed the evaporator under the dash. When the refrigerant is low, it makes sounds described as hissing, water in a pipe, or sloshing. I would check and recharge the system. It is sealed and will not lose refrigerant unless there is a leak. Very small leaks can develop over time on the seals and may actually leak more when the system is not used. If it only needs the occasional recharge (once or twice a year), I'd do that and avoid paying for costly repairs. Of course if it gets worse, you will need to find and repair the leaking component(s).
Ok I know I'm sounding dumb, but youre actually talking about the AC system right? Just want to make sure �� I hardly use the AC and last I serviced it was about 5 years ago! It still seems to work fine though, I just tried it, but that doesn't mean it doesn't have leaks. Best thing to do is take it for a service then? I topped the antifreeze, but that didn't seem to stop the sound, so must be from AC refrigerant I guess
Yes, the AC system. But, does it make the sound with the climate control system switched off? If so, then I don't believe it will be a problem with low refrigerant.
Yes, even when its off, it still makes the sound. Its really confusing. First I heard it was when I accelerated from a standstill, but when the car was stationary and revved it up I could here it as well. Not as much as when I accelerated but you can still hear it. I would describe the sound like emptying a glass of water onto the floor. Could it be something to do with the heat core? The coolant in the reservoir tank was an inch off the maximum mark, so I topped it off, but the sound is still there. I'm not sure if its because there's air trapped in the coolant, or something else thats nor related
The coolant system will self-bleed any air very quickly, so I doubt that is it. Since it happens sitting still and just revving the engine, I think we can rule out things like water trapped in the body. Can you hear the noise outside the car? If so, it may be worth investing in an inexpensive mechanics stethoscope to track it down.
At first I thought it could be water trapped in the car, but obviously when I heard it with the car stationary, I discounted that. I have to get someone to rev the engine for me to see if I can hear it from outside. But since it sounds like water I doubt what else it could be other than coolant or ac refrigerant. Its really strange. When I googled it, everyone says that it must be trapped air in the cooling system and it makes the noise passing through the heater core. I cant understand how I started hearing it just recently though. I'll check to see if I can hear it from the outside and let you know.
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